let constants = {
  COMMAND_KEYWORD: {
    REMOVE: 'rm',
    CLONE: 'clone',
    SAVE: 'save',
    UNDO: 'undo',
    REDO: 'redo',
    CLEAR: 'cls',
    LIST: 'ls'
  },
  COMMAND_TYPE: {
    ASSIGN: 'assign',
    CONNECT: 'connect',
    CREATE: 'create',
    RMNODE: 'rmNode',
    RMEDGE: 'rmEdge',
    CLONE: 'clone',
    SAVE: 'save',
    UNDO: 'undo',
    REDO: 'redo'
  },
  NODE_IDENTIFIER: {
    START: '0',
    END: 'E',
    EXP: 'e'
  },
  POS_IDENTIFIER: {
    AFTER: '@',
    BEHIND: '#'
  },
  PROPERTY_SCOPE: {
    INARGS: 'inArgs',
    OUTARGS: 'outArgs',
    ARGS: 'args',
    ALL: 'all',
    OTHER: 'other'
  },
  POS_TYPE: {
    AFTER: 'after',
    BEHIND: 'behind'
  }
};

module.exports = constants;
